Hello,
Here is an example to create a new default template in Writer, which includes your custom styles: (These instructions work for all models of OOo files. It will just adapt depending on the version installed on your position.)

You open a new blank document
You dial your settings as shown in the previous messgae

Then you select the File menu
Templates
Save

In the dialog, you define a custom name for your model, and then select the category "My Templates"
You click on OK to validate
Your model is then created

Then to assign as default document in Writer, you're in
File Menu
New
"Templates and Documents"

In the dialog box, click the button "Manage"

In the new window that appears, double click on the "My Templates"
Right click on the name of the model that you created earlier
You choose "Set as default template"
You can then close the 2 dialogs (no confirmation message is displayed)

Normally, then when you do:
File
New
Text Document
Your model with your custom styles are used automatically in Writer

If you have any remorse of conscience, you can always restore the default template Writer

File
New
"Templates and Documents"

In the dialog box, click the button "Manage"
In the new window that appears, double click on the "My Templates"
Right click the model name that you had created
You choose "restore the default template"
"Text"

Hello,
Even i am interested to have such a numbering in my document. My problem is that the document I have already almost finished. I note this for next time. But did not you a tip for the Style dialog box (F11) when I change my title (title1, title2, title3 ...) it may take into account the numbering indicated above. And then more than to automatically generate the index. But frankly I do not know if it just me or what but either openoffice or word in the time I never found the obvious function of the layout of the software.

Hello,
I looked like you as my MS Office templates used this numbering and I just found.
Menu: Format / Bullets and Numbering
Tab Options
And there you incrementing the "Full" as the levels. It is not necessarily very explicit define it, or it will nor work in you document.

Hello,
The heading styles and fleas do not have. We must not mix a title and a list is not the same semantics. A chip is a list, c is a title for a title. To properly structure a document must do so if you do not have a template:
F11 gives the window styles. Both styles use primarily, Title 1 Title 2,... Regarding the numbering on your structure, must choose Tools -> Outline Numbering. This tool is simple enough! Note however that does not mix the chips with AC under penalty of age (indeed if you set your title as smart and as a title when OpenOffice crashes.